package algorithm.algexercise.sort;

import edu.princeton.cs.algs4.*;

/**
 * Created by chengxiaoqi1 on 2018/8/6.
 */
public class SortCompare {

    public static double time(String alg, Double[] a) {
        Stopwatch timer = new Stopwatch();
        if (alg.equals("Insertion")) Insertion.sort(a);
        if (alg.equals("Selection")) Selection.sort(a);
        if (alg.equals("Shell")) Shell.sort(a);
        if (alg.equals("Merge")) Merge.sort(a);
        if (alg.equals("Quick")) Quick.sort(a);
        if (alg.equals("Heap")) Heap.sort(a);
        return timer.elapsedTime();
    }

    public static double timeRandomInput(String alg, int N, int T)
    { // 使用算法1将T个长度为N的数组排序
        double total = 0.0;
        Double[] a = new Double[N];
        for (int t = 0; t < T; t++)
        { // 进行一次测试（生成一个数组并排序)
            for (int i = 0; i < N; i++)
                a[i] = StdRandom.uniform();
            total += time(alg, a);
        }
        return total;
    }

    public static void main(String[] args)
    {
        String alg1 = args[0];
        String alg2 = args[1];
        int N = Integer.parseInt(args[2]);
        int T = Integer.parseInt(args[3]);
        double t1 = timeRandomInput(alg1, N, T); // 算法1的总时间
        double t2 = timeRandomInput(alg2, N, T); // 算法2的总时间
        StdOut.printf("For %d random Doubles\n %s is" , N, alg1);
        StdOut.printf("%.1f times faster than %s\n", t2/t1, alg2);
    }
}
